ZyXEL Communications IES-2000, Руководство пользователя

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IES-2000/3000 User’s Guide
14-2 Remote Management
Figure 14-1 SNMP Management Model
An SNMP managed network consists of two main component types: agents and a manager.
An agent is a management software module that resides in a managed device (the line card). An agent translates
the local management information from the managed device into a form compatible with SNMP. The manager is
the station through which network administrators perform network management functions. It executes operations
that control and monitor the managed devices.
The managed devices contain objects that define each piece of information to be collected about a device.
Examples of variables include the number of packets received, node port status, etc. A Management Information
Base (MIB) is a collection of managed objects. SNMP allows manager and agents to communicate for the purpose
of accessing these objects.
SNMP itself is a simple request/response protocol based on the manager/agent model. The manager issues a
request and the agent returns responses using the following protocol operations:
♦
Get
Allows the manager to retrieve an object variable from the agent.
♦
GetNext
Allows the manager to retrieve the next object variable from a table or list within an agent. In SNMP, when a
manager wants to retrieve all elements of a table from an agent, it initiates a Get operation, followed by a series of
GetNext operations.
♦
Set
Allows the manager to set values for object variables within an agent.